[Fun Science Series] The principle and making of drone | What are the effects of different shapes?

Hello, teachers and students, class has resumed Carlos must work hard to prepare STEM resources for students I remember in January I made a video Which is about the principle of drone and how to operate it After finishing the production, I have mentioned that I will use other materials to make the body But the covid19 came soon after the video was released then classes were suspended and there is no chance to do this topic Let us study this topic together today At the end of the video you will see how Carlos uses different materials to make drone bodies and you will also see the results of these drones Just a reminder, if everyone likes the channel of Carlos the OrganMan Please click subscribe in the lower right corner If you want to be notified of new videos as soon as possible Please click the bell You are also welcome to add likes and comments Let’s review it first In last episode we bought a box of DIY drone kit We installed this mini drone according to the instructions Understand that the two diagonal axes are rotating counterclockwise These two axes rotate clockwise We also study the role of the two joysticks on the remote control The right is to control forward, backward, left and right The left is to control up, down and rotation These eight actions will accelerate certain axes To produce the corresponding actions of the drone After the installation, we test the drone indoor It flied so fast without height sensor I cannot see the reaction of each move Today we try to use different materials to make drone bodies We will also tie the drone to observe its movement Let’s take a look at the components of our kit first There are motors, mainboard, battery, propellers and remote control, etc. Now we do not need the case and the battery cover We find some wood sticks and prepare two Use a piercing saw to make a cut in the middle of the two wooden sticks These two cuts become a joint Just add glue to form a cross In order to install the motors on the four corners, I found some eye screws Twist them into the four corners You can use hot glue for fixing when you DIY For example, fix the mainboard on the cross The four motors can also be fixed on the eye screws with hot glue Match the color of the motor plug with the color of the mainboard plug Red to red, white to white You can fine-tune the position and angle of the motor while the glue is still hot Make them perpendicular to the cross After fixing, plug the motor cable into the mainboard The wires can also be fixed with hot glue So as not to entangle the propellers The propellers are classified into A and B A is clockwised and B is anticlockwised Find a rubber band to fix the battery Connect the power supply and you can fly now Because there is not enough room for indoor testing so we add an eye screw under the drone Then tie the screw with a string to a heavy object We will see what happen Forward, backward, left, right, up, down, and even rotation When I was a kid, I used to tie a string the tail of a dragonfly Because there is an eye screw at the bottom of the drone It does not stand well when taking off I will add a few more eye screws It will be better for taking off You can see that I made a drone with wood sticks and it flies very well As long as the structure is good and stable Symmetrical design can be used Then we can also use other materials to make the drone Such as paper cups and plates and the old CDs I discarded Can a CD be used as a drone body? I opened a new kit to experiment Measured the diameter of the motor, it is 6.5 mm Then drill four 6.5 round holes at equal distance on the circumference of the CD Tried to insert the four motors in proper positions Still use hot glue to fix them There are no big differences from using wooden sticks Also fix the mainboard with hot glue in the middle of the CD Then connect the motor to the mainboard according to the color Feel good after connecting the wires Then you can install the A propeller (clockwise) to the motor with red plug Install the B propeller (counterclockwise) to the motor with white plug We also include the battery holder this time It is also fixed on the disc with hot glue It is more convenient to install the battery with the battery holder It’s time to connect the power and prepare for the test flight again you may guess Can this drone make with CD take off? First turn on the remote control and do the pairing Start the propeller when paired The four propellers rotate and try to take off But it can’t! why? It goes to the right. I try again! It can’t fly anyhow! why? Later I had a discussion with my colleagues Carlos finally knows why it fail You take a look at the body of the kit, it is also cross-shaped So the drone made of wood sticks performs similarly But what is the problem for a CD that is circle-shaped ? This is related to the action and reaction principle in Physics You need to know that, a drone can take off and do various actions just because the propellers generate a downward force So a reaction force is generated to lift the drone But Carlos just ignored this when choosing a CD as the body The four motors are installed on the CD The air flow driven by the rotation of the propeller is acting on the surface of the disc Instead of acting on the ground So the action and reaction force cancel each other And this is the reason why the CD drone cannot take off Although this is a failed experience But I get wise after this Carlos can use this experience in the future to teach my students how to design and 3D print the body of a drone Don’t you think this is very interestng? If you like my video Stay tuned for Carlos’s STEM class on Youtube I also hope everyone can add like and comment .